I've had the Drop key ring for five years, and I finally brought it into the store, because everyone who saw it wanted to know where I got it. Sure they're attractive and minimalistic, but they're also functional. Big enough to slide onto most wrists for easy wearing (and I have very large hands), but not bulky, so they still slide easily into pockets. You'd be hard pressed to have more keys than can fit on these things.
Bell: 3.5 x 3.25 in Bend: 4.25 x 2.25 in Drop: 4 x 3.25 in